Dust-separating fan.



J. McDANlEL. DUST SEPARATING F AN.

APPLICATI'ON FILED OCT. I8, 1915.

Patented Sept. 5, 1916.

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J. McDANIEL.

DUST SEPARATING FAN. APPLICATION FILED OCT. T8 1915.

Patented Sept. 5, 1916 4 SHEETS-SHEET 2.

J. McDANIEL.

nusr SEPARATING FAN. APPLICATION FILED OCT. 18, 1915- v I Patented Sept. 5, 1916.

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J. McDANIEL.

DUST SEPARATING FAN.

APPLICATION FILED OCT. 16.1915.

1 1 96,9 61 Patented Sept. 5, 1916.

4 SHEETSSHEET 4.

By his HZ-Zozneys 6w MM JAMES MGDANIEL, OF MINNEAPOLIS, MINNESOTA.

DUST-SEPARATI'NG FAN.

Specification of Letters Patent.

Patented Sept. 5, i916.

Application filed October 18, 1915. Serial No. 56,533.

To all whom it may concern:

Be it known that 1, JAMES MGDANIEL, citizen of the United State's, resident of Minneapolis, county of Hennepin, State of Minnesota, have invented certain new and useful Improvements in Dust-Separating Fans, of which the following is a specification.

My invention relates to dust separators of the class shown and described in my pending application for Letters Patent of the United States, Serial No. 32,316, filed June 5, 1915, and the object of my present invention is to improve the separating device of my pending case to the end that the dust collecting cones will always be kept clean and free of dust and the capacity and efficiency of the machine thereby'increased.

Other objects'of the invention will appear from the following detailed description.

The invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claims.

Figure 1 is a vertical sectional view through a dust separator embodying my in vention, Fig. 2 is a similar view on a section line at right angles substantially to the section line of Fig. 1, Fig. '3 is a detail sectional view of the fan and the cones on one side thereof, Fig. 4 is an enlarged sectional view, showing the manner of mounting the outer cone, Fig. 5 is a similar View, show.- ing the manner of mounting the inner cone, Fig. 6 is a perspective view, showing the frictional drive device between the inner and outer cones, Fig. 7 is a view looking at the inner ends of the cones, showing the friction clutch devices and the wall in cross section with which they engage. Fig. 8 is an end view of the outer cone, Fig. 9 is an end view of the inner cone, showing the partitions and flights thereon, Fig. 10 is an end view of the innercone, showing the bearing ring at the inner ends of the partitions, Fig. 11 is a perspective view of one of the clutch members.

In the drawing, 2 represents the casing of the machine, in which my improved dust separator is mounted. It may be used in connection with a purifier or any other machine in which it is desirable or advantapulley 5.

geousto use a dust separator of this type. 3 is a shaft, having bearings 4 in the machine frame and provided with a driven Mounted on this shaft isa blast fan 6 having a casing 7 provided with central openings or eyes 8. This casing has an air trunk 9 communicating therewith and in this air trunk I prefer to arrange an inverted cone-10 forming an air diffuser or regulator. This cone is adjustable in the open end of the trunk by means of a band 11 having a clamping device 12 and straps 13 connecting the band with the cone. Upon loosening this band the cone may be raised or lowered to increase or decrease the area of the opening between the cone and the walls of the trunk. In Fig. 1 the cone is shown in its open position. The draft of air through the'machine can be easily regulated by the adjustment of the cone.

I The fan casing is supported in the machine frame by suitable means, such as arms 14. The shaft is provided with right and left hand threads on each side of the fan casing with which the interiorly threaded hubs 15 engage and are held in place by collars 16. The inner ends of the hubs are provided with inwardly projecting flaring flanges 17 and the outer ends of the hubs have bearings for the hubs of spiders 18. These spiders are free to revolve on the hubs and are provided with flanges 19 which flare inwardly and outwardly parallel with the flanges 17. Hubs 20 are loosely mounted on the shaft 3 upon each side of the fan casing and adjacent thereto and are provided with radial webs 21 terminating in inwardly turned flanges 22. To these flanges and to the flanges 17 the cones 23 are secured to revolve with the shaft 3. j

Spiders 24 have bearings at 25 on the hubs 20 and the peripheries of these spiders are provided with flanges 26 concentric with the flanges 19 and to these flanges 19 and 26 the outer cones 27 are secured. These outer cones 27 are concentric with the inner cones and spaced therefrom but are not positively driven, as is the case with the inner cones.

Between the spiders 24 and the webs 21 recesses 28 are formed to receive semi-circular friction shoes 29, each having slots 30 therein to receive pins 31 mounted in the webs 21. These shoes are positioned to conpassage.

tact with outwardly projecting flanges 32 formed on the spiders 24 there being sufficient friction created between the shoes and these flanges to move the spiders 24 and with them the outer cones.

The faces of the friction shoes are preferably leather covered and as the entire cone is rapidly revolved, the shoes will be thrown out by centrifugal action to engage the inner faces of the flanges and drive the outer cones with a slight slippage or creeping of the shoes to obtain a differential or variation in the travel of the cones. This manner of driving the outer cones from the inner cones provides for the proper degree of slippage commensurate with the speed of the cones, which increases or decreases proportionately to the speed of the fan.

The object in varying the travel of the cones in a given period, or obtaining a differential between them, is to provide for a thorough cleaning of the inner surface of the outer cone and prevent the dust from adhering thereto and gradually clogging the A series of partitions 33 are secured to the inner cones and extend lengthwise thereof and radiate therefrom with their outer edges in position to sweep or scrape the inner surfaces of the outer cones as the inner cones are revolved. The difference in travel of the inner and outer cones I prefer to make approximately one full revolution to each 80,000 revolutions of the fan, or about one revolution per hour, and as each partition brushes or scrapes the inner surface of the outer cone one complete revolution, the difierential specified will provide for cleaning the surfaces through the engagement of the partitions therewith sixteen times in one hour; that is, assuming that the differential is one full revolution in an hour. Of course, the number of partitions may be increased or diminished, as desired.

To make a more complete separation, I prefer to secure angle plates 34 transversely to said partitions, radiating from the inner cones and having inner end portions 35 fastened securely to said inner cones. These angle plates form riffies along the face of the partitions and eddies of dust are created thereby and thrown outwardly by centrifugal force against the outer cones, thereby effecting a more complete separation, and I have found that by using these rifiies I could reduce the speed of the fan very materially and still obtain substantially the same results. These rifHes, therefore, serve a twofold purpose. They effect a more complete separation of the dust from the air and allow reduction in speed of the fan without disastrous results, and at the same time brace and stiffen the partitions and permit the use of comparatively thin sheet metal in the construction of the partitions.

At the inner ends of the partitions 33 I provide annular rings 36 and plates 37 seoured to the spiders 24 and opposite the plates 37 and on said spiders I mount flanges 38 projecting inwardly toward and adjacent to the walls of the fan casing and serving as guards to prevent the dust from being drawn through the eyes of the easing into the fan. Between the plates 37 and the outer cones narrow annular gaps 38 are formed, through which the dust held outwardly by centrifugal force against the inner surfaces of the outer cones is directeu, the flare of the cones aiding materially in accelerating the movement of the dust from their outer toward their inner ends.

Between the inner ends of the outer cones and the walls of the casing I provide comparatively narrow dust passages or gaps 39, communicating with a chamber 40 which encircles the fan casing. The dust will pass through thesegaps and with it a portion of the air into the chamber 40. The air will travel around in this chamber 40 at substantially the same speed as the cones and a cyclonic action will be established and the dust whirled around on the outer side of the air currents against the wall of the chamber and'caused to pass through an opening 43 leading to a dead air chamber 44. A considerable portion of the air will escape through the passages 41 into the machine casing and mingle with the currents entering the cones. A portion of the air will pass into the dead air chamber, creating sufiicient pressure therein to overcome the pressure at the port 45 and allow the air in the chamber 44 to flow back into the chamber 40 through the passage 45, while the dust will settle to the bottom of the chamber 44. I have found that the entrance of dust into the dead air chamber is greatly facilitated by allowing a portion of the air to enter this chamber and as an exhaust is necessary, I have found that a small passage 45 permits the air to flow back into the chamber 40, the volume depending, of course, upon the size of the passage. Should any dust be carried through the passage 45 back into the chamber 40, it will circle i around in the chamber and finally settle in the dust spout.

As in my former application, above referred to, the air passages between the cones increasing in area inwardly, allow the incoming air currents to spread out as they approach the fan, casing and the revolution of the inner cone will cause the dust particles to be thrown outwardly by centrifugal force and their specific gravity in effect multiplied many times, the light, as well as heavy particles, clinging to the surface of the outer cone and gradually working inwardly, being prevented from adhering to the cone by the scraping action of to the inner cone and mounted to barely clear the surface of the outer cone. The engagement of the friction shoes will drive the outer cone and there will be suflicient creeping or slippage to allow the inner cone to gain approximately a full revolution on the travel of the outer cone in an hours operation of the machine; that is, assuming the fan is operated at a speed of about 1400 revolutions per minute and that the mechanism is in normal working order. This slight differential in the travel of the cones will have the efiect of causing the inner surface of the outer cone to be swept by the partitions and all the accumulated fine dust cleaned OE and directed by the flaring walls of the cones inwardly to the discharge gaps.

I claim as my invention:

1. A dust separator comprising a fan and casing, cone-shaped members concentrically mounted and having a dust intake passage between them, said inner member being mounted to revolve with said fan, a frictional drive between said inner member and said outer member, to provide a diflerential in travel between them, and said inner member having means for sweeping the inner surface of the outer member, a narrow gap or dust passage being formed between said outer member and the wall of said casing, through which gap dust is directed by centrifugal force.

2. A dust separator comprising a fan and casing, a shaft for said fan, a cone-shaped member mounted on said shaft, a second coneshaped member concentric with said first named member and outside the same and spaced therefrom to form a dust intake passage between them, said outside member having a frictional driving connection with said inner member to provide a differential in travel, said frictional driving connection including shoes mounted in said inner cone and having a radial movement, and a flange carried by the outer cone in the path of said shoes, and means for sweeping the inner surface of the outer member.

3. A dust separator comprising a fan and casing having an intake opening, a coneshaped member concentric with said fan and opening and mounted to revolve with said fan, a second cone-shaped member encircling said first named member and spaced therefrom and having a differential driving connection therewith, and partitions mount ed on said first named member to sweep the inner surface of the outer member. v

4. A dust separator comprising a fan and casing, concentric cone-shaped members spaced apart and mounted'to revolve, the inner cone-shaped member having partitions for sweeping'the inner surface of the outer member and riifle plates mounted on said partitions radiallywith respect to said inner member.

5. A dust separator comprising a fan and casing therefor, nner conesmounted on said fan shaft, outer con'es having a differential drlvmg connection wlth said'inner cones,

partitions mounted on said inner cones and running lengthwise thereof and having their outer? edges in position to sweep the inner surface of theouter cones, and angle plates mounted transversely on said parti tions. v 1

6." A dust separator comprising a fan, a casing therefor having inlet openings, coneshaped members mounted to revolve on opposite sides of said casing, and concentrically arranged and having dust intake passages between the inner and outer members, the dust passing between said members being subjected to centrifugal force and thrown outwardly against the inner surfaces of the outer cone-shaped members, the inner portion of'said passages having dust exit openings and the outer cone-shaped member on each side of said casing having a frictional driving connection with the inner members to revolve a less number of times in a given period than the inner members, and means carried by the inner members for sweeping the inner surfaces of the outer members.

7. A centrifugal dust separator comprising a fan and a casing therefor, cones concentrally mounted and spaced apart to form a dust passage between them and encircling the eye of said fan casing, said cones having a frictional driving connection between them whereby they will be operated at a differential speed, the outer cone being driven from the inner one, a comparatively narrow dust gap being provided between the inner end of the outer cone and the wall of said casing,

said dust gap communicating with the space 4 between said cones and to whichgap the dust thrown by centrifugal force against the inner surface of the wall of said outer cone is directed by said wall, the relative movement of said outer cone and said casing preventing the dust from clogging or bridging in said gap, and said dust passage also communicating with the eye of said fan, substantially as described.

8. A centrifugal dust separator comprising a fan and casing therefor, said casing having eyes in the opposite sides thereof,

inner and outer cones concentrically mounted upon opposite sides of said casing and encircling said eyes, the outer cones being spaced from the inner cones to form a dust passage between them and the outer cones, comparatively narrow gaps or passages being formed between their inner ends and the walls of said casing to which passages the dust thrown by centrifugal force against the outer cones is directed by the flaring walls thereof, said passages also communicating with the eyes of said casing, friction shoes mounted for radial movement on said inner cones, and flanges carried by said outer cones and encircling said friction shoes and engaged thereby to drive said outer cones when thrown out by the revolution of said inner cones.

9. A dust separator comprising a fan and a casing therefor having an air inlet open ing, members concentrically mounted adjacent to said opening and having a dust intake passage between them through which the dust laden air is drawn by the revolution of said fan, a comparatively narrow dust gap being formed at the inner end of said outer member and having relatively movable walls whereby clogging of the dust in said gap is prevented, said members being mounted for differential revolution, the inner member having means for sweeping the inner surface of the outer member.

In witness whereof, I have hereunto set my hand this 4th day of October, 1915.

JAMES MoDANIEL.

Witnesses JAMES RICHMOND, FRANCIS CHAPMAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. G. 

